Puppy Training Pads- Westie?

hi, i am bringing my westie puppy home in a couple of weeks and i don’t know what to get.
are puppy training pads a good idea?
do you put them in the crate or on the floor?
what size would you get for a westie pup? small medium or large?
Does anyone know where i can get the best deal on the pads?
thankyou x